Can a Simple Glass Lens Focus White Light Correctly?

In summary, the property of refraction in a transparent material makes it useful for a lens. However, a simple glass lens placed under white light cannot correctly focus an image due to the interference of different wavelengths of light passing through the lens. This is why a glass prism is used to split white light into different colors. Interference between light of the same wavelength causes refraction.
  • #1
jakey
51
0

Homework Statement


The property of a transparent material that makes it useful for a lens is: this is refraction, right?

In relation to this, the image of an object can't be focused correctly if a simple glass lens is placed under white light because:
a)the lens absorbs light
b)the glass has some coloration due to impurities
c)the surface of the lens reflect some light
d)a glass prism splits sunlight into different colors
e)glass absorbs UV light


Homework Equations



none

The Attempt at a Solution


I'm thinking that the answer is D. This is because white light contains many wavelengths, it is not monochromatic. Because of this, when they pass through the lens, some of the wavelength may interfere. This is why it can't be focused correctly.

In relation to this, white light is split into different colors when it passes thru the prism.

is this right? thanks
 
Physics news on Phys.org
  • #2
jakey said:
I'm thinking that the answer is D. This is because white light contains many wavelengths, it is not monochromatic. Because of this, when they pass through the lens, some of the wavelength may interfere. This is why it can't be focused correctly.

In relation to this, white light is split into different colors when it passes thru the prism.

is this right? thanks

Hi jakey! :smile:

D is right, and your reason "it can't be focused correctly" is also right …

but your reason why it can't is wrong …

I suggest you re-think "some of the wavelength may interfere" … isn't interference what makes lenses work?

and can two different wavelengths of light interfere? :wink:
 
  • #3


tiny-tim said:
Hi jakey! :smile:

D is right, and your reason "it can't be focused correctly" is also right …

but your reason why it can't is wrong …

I suggest you re-think "some of the wavelength may interfere" … isn't interference what makes lenses work?

and can two different wavelengths of light interfere? :wink:

really? i would just like to clarify first, refraction also happens in a lens right?

isn't it that when they pass through the lens, some of the wavelenghths may be out of phase and thus some would cancel, some would interfere constructively?
 
  • #4
jakey said:
really? i would just like to clarify first, refraction also happens in a lens right?

isn't it that when they pass through the lens, some of the wavelenghths may be out of phase and thus some would cancel, some would interfere constructively?

yes, interference between light of the same wavelength causes refraction etc :smile:
 
  • #5


tiny-tim said:
yes, interference between light of the same wavelength causes refraction etc :smile:

and because white light isn't monochromatic, then it can't be focused correctly. thanks!:)
 

What is lens refraction?

Lens refraction is the bending of light as it passes through a lens, causing the light rays to change direction. This is what allows lenses to focus and create an image.

How does lens refraction affect vision?

Lens refraction plays a crucial role in vision by allowing the eye to focus and create clear images. Without refraction, the light rays entering the eye would not be properly focused, resulting in a blurry image.

What are some common lens refraction problems?

Some common lens refraction problems include nearsightedness (myopia), farsightedness (hyperopia), and astigmatism. These conditions occur when the eye's lens is unable to properly refract light, resulting in vision problems.

How are lens refraction problems corrected?

Lens refraction problems can be corrected with the use of corrective lenses, such as glasses or contact lenses, which are designed to bend light in a way that compensates for the eye's refractive error. In some cases, surgery may also be an option.

Can lens refraction problems be prevented?

In some cases, lens refraction problems may be prevented by maintaining good eye health and avoiding activities that can strain the eyes, such as prolonged screen time. However, some conditions, such as myopia, may be hereditary and cannot be prevented.

Similar threads

  • Introductory Physics Homework Help
Replies
2
Views
2K
  • Introductory Physics Homework Help
Replies
1
Views
2K
  • Introductory Physics Homework Help
Replies
1
Views
8K
  • Introductory Physics Homework Help
Replies
22
Views
2K
Replies
1
Views
1K
  • Introductory Physics Homework Help
Replies
4
Views
2K
  • Introductory Physics Homework Help
Replies
3
Views
2K
  • Introductory Physics Homework Help
Replies
2
Views
2K
  • Biology and Medical
Replies
11
Views
3K
  • Introductory Physics Homework Help
Replies
1
Views
2K
Back
Top